Clinicopathological predictors of repeated recurrence in sinonasal inverted papilloma.

Purpose: To evaluate association between clinical and pathological findings and repeated recurrence in sinonasal inverted papilloma.

Methods: Retrospective cohort study conducted at a tertiary care teaching hospital included all patients operated for inverted papilloma from January 2010 to December 2019. Patients were categorized as primary and recurrent cases. Based on disease status at follow-up, they were subcategorized into 'primary with no recurrence' (PnR), 'primary with recurrence' (PwR), 'recurrent with no further recurrence' (RnR), and 'recurrent with further recurrence' (RwR) groups. Data including demography, clinical, endoscopic and pathological findings were collected and analyzed.

Results: Increased incidence of pale appearance of lesion in RnR group (p = 0.017), polypoidal appearance in primary group (p = 0.002) and fibrous appearance in the recurrent group (p = 0.002) were statistically significant. Predominant epithelium was combined respiratory and squamous epithelium in primary and recurrent groups and also in RnR group (p = 0.019), while it was squamous (p = 0.024) in RwR group. Epithelial hyperplasia was more common in primary and RnR groups. Oncocytic change, cystic dilatation, microabscess and squamous metaplasia were seen more in recurrent and RnR groups. Cytoplasmic glycogenation was more in recurrent and RwR groups. Stroma was predominantly edematous in all the groups.

Conclusions: Patients with recurrence are younger and present earlier than those with primary disease. Fleshy appearance and pink/red colour of tumour, lining epithelium being squamous and cytoplasmic glycogenation could be considered as features predicting recurrence. Negative predictors of recurrence of IP include pale appearance of tumour, combined respiratory and squamous epithelium lining and squamous metaplasia.